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COMMITMENTS AND CONTINGENCIES - Southbridge Landfill Environmental Remediation Liability (Details) - Southbridge Landfill - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Accrual for Environmental Loss Contingencies [Roll Forward] |  |
Beginning balance | $ 5,173 | $ 5,936
Accretion expense | 94 | 116
Obligations settled | (556) | (612)
Ending balance | $ 4,711 | $ 5,440

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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